package com.tj.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.util.List;


@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    /**
     * 放行静态资源
     * @param registry
     */
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {

    }

    /**
     * mvc消息转换器
     * @param converters
     */
    @Override
    public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
        //1.创建消息转换器对象
        MappingJackson2HttpMessageConverter messageConverter = new MappingJackson2HttpMessageConverter();

        //2.设置对象转换器，底层使用Jackson将java对象转换为json
        try {
            messageConverter.setObjectMapper(new JacksonObjectMapper());
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        }

        //3.将上面消息转换器对象追加到mvc框架的转换器集合中
        converters.add(0,messageConverter);
    }
}
